Microtubule destabilizing agent-2 (Compound 21) is an orally active and selective antitumor compound targeting microtubule protein. Microtubule destabilizing agent-2 destabilizes microtubule proteins and inhibits microtubule polymers. Microtubule destabilizing agent-2 arrests the G0/G1 phase in human tumor cells. Microtubule destabilizing agent-2 induces Apoptosis by activating the cascade pathway of caspases. Microtubule destabilizing agent-2 has anti-inflammatory activity, as inhibiting TNF-α and IL-6 in vitro. Microtubule destabilizing agent-2 reduces tumors growth in xenograft mice.